Picture this: You’re watching the evening news when footage appears of what looks like a tornado, but it’s glowing red and orange with flames spiraling hundreds of feet into the sky. It seems impossible, something from a disaster movie. Yet true fire tornadoes are rare and are always associated with extreme fire behavior. These spinning funnels of flame represent one of nature’s most spectacular and terrifying phenomena.
Fire tornadoes aren’t just regular fires with a fancy name. A fire whirl, fire devil or fire tornado is a whirlwind induced by a fire and often (at least partially) composed of flame or ash. These start with a whirl of wind, often made visible by smoke, and may occur when intense rising heat and turbulent wind conditions combine to form whirling eddies of air. These incredible events challenge our understanding of both fire behavior and atmospheric science.
The Perfect Storm of Conditions
Fire tornadoes don’t just happen anywhere or anytime. The ingredients that create fire whirls are heat, rotating air, and conditions that stretch out that rotation along its axis, making it stronger. Think of it like a recipe where every ingredient must be perfectly measured and timed.
Initial Updraft: The intense heat from the fire creates a strong updraft of hot air and combustion gases. Vorticity Introduction: Wind shear or topographic features introduce rotation into the rising air column. Stretching and Intensification: As the rotating column stretches vertically, it intensifies due to conservation of angular momentum. The landscape itself plays a crucial role, with mountains, valleys, and canyons creating wind patterns that can either fuel or prevent these phenomena. Sometimes a certain topography will restrict airflow in such a way that a spiral pattern develops.
The Science Behind the Spectacle
The physics of fire tornadoes mirrors that of dust devils, but with a deadly twist. Superheated air above the blaze rises rapidly in columns or, to use firefighter speak, in plumes. As the air rises, it begins to rotate, drawing in more air and slowly drawing the flames upward in a tight spiral. However, what makes fire tornadoes unique is their source of energy.
The fire produces extreme heat, which causes the air above it to rise quickly. This rising hot air is called an updraft. The hotter the fire, the stronger the updraft. When wind shear enters the equation, the real magic happens. A wind shear occurs when the wind changes speed or direction with height. This causes the air to spin as it rises, twisting the rising air into a vortex and producing a rotating column of fire.
Size Matters: From Miniature to Monstrous
Not all fire tornadoes are created equal. Most fire whirls stay small — a foot or two in diameter. But some can grow to be 400 feet (122 meters) tall and 50 feet (15 meters) wide. In other words, they can assume proportions of a small tornado. The smallest ones might barely register as noteworthy, while the largest become forces of nature.
They are usually 10–50 m (33–164 ft) tall, a few meters (several feet) wide, and last only a few minutes. Some, however, can be more than 1 km (0.6 mi) tall, contain wind speeds over 200 km/h (120 mph), and persist for more than 20 minutes. The most extreme examples can reach temperatures exceeding 2,000 degrees Fahrenheit. A fire whirl can reach up to 2,000 °F (1,090 °C), hot enough to melt steel and instantly ignite most materials.
When Fires Create Weather Systems
Perhaps the most fascinating aspect of fire tornadoes is their ability to generate their own atmospheric conditions. According to Lareau a fire tornado “initiates its own weather system helping to concentrate the rotation”. As smoke rises and condenses in the upper atmosphere, it forms an ice-topped cloud known as a pyro-cumulonimbus or firestorm cloud over the fire vortex. The development of the cloud stretches the underlying column of air, concentrating the rotation near the surface and causing winds to accelerate to tornado strength.
If the fire is big enough, it will form a pyrocumulonimbus, or a “fire storm cloud.” These can produce lightning, which could set off even more fires. They also generate stronger winds, which fan the fire, making it hotter and helping it spread. It’s like nature creating its own feedback loop of destruction. They remain tethered to the fire that spawned them, spewing embers and lightning that continue to fuel the fire. These clouds also tend to produce lightning with a positive rather than negative charge, which makes the storm last longer, and they rarely form rain to help extinguish a wildfire.
The Three Types of Fire Whirls
Scientists have classified fire whirls into three distinct categories based on their formation and behavior. There are currently three widely recognized types of fire whirls: Type 1: Stable and centered over burning area. Type 2: Stable or transient, downwind of burning area. Type 3: Steady or transient, centered over an open area adjacent to an asymmetric burning area with wind.
Type 1 whirls are the most predictable, remaining relatively stationary over the fire source. Type 2 forms downwind and can travel away from the main fire, creating new ignition points. Type 3, perhaps the most dangerous, develops in open areas adjacent to fires and can move unpredictably. There is evidence suggesting that the fire whirl in the Hifukusho-ato area, during the 1923 Great Kantō earthquake, was of type 3. This massive event killed thousands and demonstrated the devastating potential of these phenomena in urban settings.
Historical Devastation and Modern Examples
Fire tornadoes have left their mark throughout history, often during humanity’s darkest hours. Fire whirls were produced in the conflagrations and firestorms triggered by firebombings of European and Japanese cities during World War II and by the atomic bombings of Hiroshima and Nagasaki. These events showed how intense urban fires could create their own terrifying weather systems.
More recently, California has witnessed some of the most powerful fire tornadoes ever recorded. During the Carr fire near Redding in July 2018, a fire tornado spinning at speeds of up to 143 miles an hour was responsible for four of the eight deaths associated with the fire. This particular tornado achieved EF3-level wind speeds, equivalent to a significant regular tornado. During the 2003 Canberra bushfires in Canberra, Australia, a violent fire whirl was documented. It was calculated to have horizontal winds of 160 mph (260 km/h) and vertical air speed of 93 mph (150 km/h), causing the flashover of 300 acres (120 ha) in 0.04 seconds. It was the first known fire whirl in Australia to have EF3 wind speeds on the Enhanced Fujita scale.
Climate Change and Increasing Frequency
As our planet warms, the conditions that create fire tornadoes are becoming more common. Persistent heat waves that dry out the land and vegetation have increased the potential of wildfires to be more violent and widespread. Global warming has modified the Earth’s climate in ways that profoundly affect the behavior of wildfires. Longer fire seasons and more intense blazes create perfect breeding grounds for these atmospheric monsters.
A 2021 study in Science Advances suggests that climate change is creating more days with ideal conditions for extreme fire behavior, including fire tornadoes. Research published in Environmental Research Letters (2023) indicates that the “fire season” is lengthening in many parts of the world, potentially increasing the window for fire tornado formation. While scientists can’t yet prove direct causation, the correlation is concerning. The data’s too young to be sure, he said, but it is plausible fire tornadoes are occurring more often as fires grow more intense and the conditions that create them more frequent.
Why These Storms Are Nature’s Rarest
Despite increasing wildfire activity, fire tornadoes remain extraordinarily rare events. National Weather Service Meteorologist Julie Malingowski said fire tornadoes are rare, but do happen. Their rarity stems from the precise alignment of conditions required for formation. The only requirement, then, is a large amount of dry fuel and an intense blaze concentrated in a relatively small area. When these conditions are met, fire tornadoes are likely to form.
However, “likely” is relative in atmospheric science. In the real world, it’s hard to say how frequently fire whirls or tornadoes happened in the past, since they often occur in remote areas with no one around. Many probably form and dissipate without human observation. Fire tornadoes are still a bit of a mystery because they involve many factors. For starters, they’re rare. Studying them requires getting close, which is dangerous. They also need the right conditions to form: a combination of intense heat, dry fuel, and wind shear. This makes them unpredictable, so scientists haven’t fully figured out how all the pieces fit.
Conclusion
Fire tornadoes represent one of nature’s most extreme displays of atmospheric power. These rare phenomena occur when intense heat, precise wind conditions, and adequate fuel sources align in a perfect storm of destruction. Fire tornadoes stand as a testament to the raw power of nature, combining the destructive forces of fire and wind into a phenomenon that seems almost supernatural. As we’ve explored, these events are not just visually spectacular but also incredibly dangerous, capable of dramatically altering wildfire behavior and posing severe risks to life and property.
As climate change continues to create conditions more favorable to extreme fire behavior, understanding these phenomena becomes increasingly critical for firefighter safety and public preparedness. While we may never be able to prevent fire tornadoes, our growing knowledge helps us better predict when conditions might be right for their formation. What fascinates you more about these natural phenomena: their incredible power or their mysterious rarity? Tell us in the comments.
